CHP splits with motorcycle lane guidelines

It's rush hour on Highway 101, and up ahead traffic is slowing. Car after car shifts from a zoom to a cruise to a roll. For a car or truck driver, there is no way to avoid the jam, other than taking side roads through town.

But for a motorcyclist riding on the highway through Marin County, the gridlock is not quite so ominous. Thanks to a state law that allows lane-splitting — California is the only state that allows it — motorcyclists can weave through the traffic, driving in whatever available width there is, and pass by the velocity-challenged drivers sitting in automobiles.

Nothing has changed — or is expected to change — with the law that has for decades provided motorcyclists a perk. But a recent squabble over the California Highway Patrol's lane-splitting safety guidelines has raised questions over what is safe lane-splitting and whether there should be some sort of standard.

"I'm a little confused," said John Harper, owner of MotoHaven, a Harley Davidson rental and repair shop in Novato. "The guidelines are good. Or were. Why was it a big deal to have them, then pull them?"

Guidelines removed

The Highway Patrol posted the guidelines on its website in March 2013. But in July of this year, the guidelines were removed at the suggestion of the state Office of Administrative Law, which is charged with making sure regulations are clear and available to the public. It also oversees publication and distribution of regulations.

"Some people had interpreted them as rules, laws, regulations that could be enforced," said Highway Patrol spokeswoman Jaime Coffee. "They were not intended for that purpose. They were prepared as common-sense safety tips."

The Department of Motor Vehicles and the Office of Transportation Safety, which had followed the Highway Patrol's lead by posting the guidelines, also removed them in response to the administrative law office's suggestion.

Administrative law Director Debra Cornez said the removal was prompted by a citizen petition challenging the guidelines as "an underground regulation."

Motorcyclists said the guidelines aligned with what they generally practice anyway: don't go more than 10 mph faster than the flow of traffic, don't lane-split if traffic is moving faster than 30 mph, and try to limit the practice to the two left lanes.

Dave Pearson, a motorcyclist and sales associate at the motorcycle-centric Marin Speedshop in San Rafael, said he had not been aware of the guidelines' specifics. But when he listed off his "personal guidelines," they aligned with the Highway Patrol's now-expunged suggestions.

"There are people who are excessive," Pearson said. "But it's usually kids or crazy people."

It's those motorcyclists who don't adhere to what Pearson called "unwritten rules" that give motorcyclists and lane-splitting a bad reputation, he said.

Benefits claimed

Mill Valley motorist Roxanne Partridge said she is fine with lane-splitting. But she is wary of the occasional motorcyclist who zigzags through traffic precariously.

"It's kind of silly when they're not being careful," Partridge said. "Or if they're on a more quiet bike, then it can be difficult to know they're coming."

Guidelines or no guidelines, motorcyclists say lane-splitting benefits all drivers on the road — and they hope it remains legal.

"It's a privilege, a cool thing to have," Pearson said.

The obvious advantage for motorcyclists is that they are able to get to their destinations sooner, as they move faster than their four-wheeled counterparts. And by moving along in this fashion, that helps reduce congestion, motorcyclists say.

Pearson said he sees about a dozen motorcyclists on the freeway during his commute to San Rafael from San Leandro. If those motorcycles weren't lane-splitting, that would mean 12 more vehicles clogging the road during a traffic jam on Interstate 880 — a freeway notorious for long commutes.

Then there is the mechanical benefit of lane-splitting. Most motorcycle engines are air-cooled, so they rely on convection created by wind passing over the engine as the motorcycle is in motion. If a motorcycle sits idly or is not moving fast enough to get a significant airflow over the engine, it could overheat.

Harper said if he were riding his hog in a hot place, such as Texas in the summer, he would be inclined to pull over and have an iced tea, rather than continue sitting in traffic.

Engine cooling was an early reason for allowing lane-splitting. But when state legislators considered outlawing it in the early 2000s, Highway Patrol officials lobbied against the new law, using accident fatality rates to show that lane-splitting helps save lives. They argued that a stationary or slow-moving motorcycle is more vulnerable to rear-ending by absent-minded drivers who fail to brake for traffic.

Considering what is at stake for motorcyclists — any accident on the road poses a grave threat — road safety tends to be a priority, and it is what, with most riders, governs them to split lanes with caution — guidelines or no guidelines.

"At the end of the day, motorcyclists have more to lose," Pearson said. "What's the worst that can happen to a car? A side mirror gets knocked off, a scratch. A motorcycle can go under a car."